21668982 has 32 divisors (see below), whose sum is σ = 46332000. Its totient is φ = 6732288.

The previous prime is 21668963. The next prime is 21669007. The reversal of 21668982 is 28986612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10144 + ... + 12092.

It is an arithmetic number, because the mean of its divisors is an integer number (1447875).

Almost surely, 2^21668982 is an apocalyptic number.

21668982 is an abundant number, since it is smaller than the sum of its proper divisors (24663018).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21668982 is a wasteful number, since it uses less digits than its factorization.

21668982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2080.

The product of its digits is 82944, while the sum is 42.

The square root of 21668982 is about 4654.9953813081. The cubic root of 21668982 is about 278.7914835672.

The spelling of 21668982 in words is "twenty-one million, six hundred sixty-eight thousand, nine hundred eighty-two".